Fairfax County school officials are seeking public input on possible scenarios for later high school start times.

At a community meeting Tuesday, the discussion of the proffered proposals exposed a sharp divide between those pushing for a change and those who want to keep the status quo.

High schools would start from 30 minutes to almost two hours later under the four options presented to the audience at Tuesday’s forum. More than 200 people crowded around tables in the Langley High School cafeteria were asked to weigh the benefits and challenges of each approach, though some argued for a fifth option: none of the above.

A move to a later morning bell for high schools has long been a contentious issue in Fairfax County.

For 10 years, the parent-led SLEEP (Start Later for Excellence in Education) has advocated for a change. One of its founders, Sandy Evans, now sits on the School Board, but still any plans for later start times have stagnated.

Although previous attempts have been unsuccessful, in April 2012 the School Board voted 10-2 to set the goal of starting high schools after 8 a.m. Most county high schools currently start at 7:20 a.m., and buses pick up some high school students as early as 5:45 a.m.

The school system contracted a research team to develop plans for achieving this goal on April 13. The four proposals presented at the community meetings are the fruit of the research team’s labor.

After gathering feedback from parents, students, faculty, community members, the research team will submit a final recommendation to the School Board in July. The vote is planned for October, with any changes taking effect in the 2015-16 school year.

Tuesday’s event was the second of eight planned meetings. The rest are scheduled to take place across the county over the next three weeks.

Advocates for later start times point to scientific studies cataloging the benefits of sleep for teenagers: stronger mental and physical health, increased academic performance and reduced risk of drowsy driving.

Psychologist Danny Lewin, co-director of the Children’s National Medical Center research team hired by the school system, said to the audience that a teenager’s very biology rebels against waking up early.

“From our perspective, to make no change would be to do harm,” Lewin said.

Yet opponents worried about the effects of later start times on after-school activities. If high schools started at 9:15 a.m., the school day would not end until 4:05 p.m. With athletic practices or band rehearsals pushed later in the day, students could find themselves with less time in the evenings for homework or relaxation.

Others expressed concern about transportation, from high school commuters jamming roads during morning rush hour to changes in dropoff and pickup schedules for parents.

Parents and students in favor of a change preferred the two options that would maximize student sleep, with high schools starting at 8:30 a.m. or 9:15 a.m. The other two options placed high school start times around 8:10 a.m.

“I definitely think we need a change,” said Hanna Hunt, a junior at Langley. “There are more benefits than challenges, especially when you look at it from the student health perspective.”